Internal-combustion engine.



J. R. ROGERS.

INTERNAL coMBusTroN ENGINE.

APPLICATION FILED JULY 9, 1910.

Patented July 4, 1916.

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INTERNAL COMBUSTION ENGINE.

APPLICATION FILED IULYQ. 1910.

Patented July 4, 1916.

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APPLICATION FILED 1uLY9 1910 Patentd July 4, 1916.

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J. R. ROGERS. INTERNAL COMBUSTION ENGINE. APPLICATION FILED IuI.Y9.1910.

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Patented July 4. 1916.

JOHN R. ROGERS, OF BROOKLYN, NEW YORK.

ITERNAL-COMBUSTION ENGINE.

Application lei July 9, 1910. Serial No. 571,142.

To all whom z't may concern:

Be it known that I, JOHN R. ROGERS, a citizen of the United States,residing in the borough of Brooklyn, county of Kings, and State of NewYork, have invented certain new and useful Improvements in Internal-Combustion Engines, of which the following is a specification.

My invention relates to internal combustion engines, and the object isto provide an engine of the two cycle or two phase type which shall besimple in construction and which shall provide a more certain means ofobtaining a regular and eflicient action of the engine. One means ofattaining this object is secured by a certain scavenging of air previousto the introduction of the explosive charge and consists in certainarrangements and relations of the parts to accomplish this object aswill be hereinafter described.

Other objects and advantages will appear from the'following descriptiontaken in connection with the accompanying drawings which illustrate onemeans of carrying out.

my invention.

I have shown my invention as applied in a. form adaptedy for useespecially in connection with an automobile or amotor boat,v

but it can be applied 'to other purposes without change of the principleinvolved.v

In the drawings Figure ,1 is fa vertical sectional view through thecenter ofthe cylinder and the crank case of van engine con'- structedaccording to my invention, show- Specieation of Letters Patent.

Patented July 4, 1916.

Fig. 7 is a vertical sectional view along line 7-7 of Fig. 6.

Similar letters of reference indicate similar parts throughout theseveral views.-

vA A indicate twin cylinders formed of a slngle casting, the cylindersbeing separated from each other by a wall B and having a commonexplosion chamber C atthe upper end of the cylinders.

'D represents a crank case on which the cylinders A, A. are supportedandv to which they are fastened by any suitable means, such as bolts DD.

The cylinder casting is provided with water chambers E, E 1n its -wallsand the wall B is provided with suitable water chambers E', E. .V Thecylinders A, A are offset with relation to the crank shaft F in order toobtain a differential motion of thel working pistons G,- G. lVorkingpiston G ing the parts when the explosive chargeis compressed and readyto beexploded. Fig, 2 'is a view similar to Fig. 1show1ng the workingpistons near the lower end of theirmovement, the left had working pistonhaving reached its extreme downward movement and the right hand working'piston approaching the'end of its movement. Fig. 3 is a similar view toFig. 1, showing the left hand working piston beginning lts re- 'turn andthe right hand Vworking piston having 'reached the eXtreme limit ot itsmovement. Fig. f4 is a transverse sectlonal view along line 4-4 of Fig.l. Fig. 5 1s a transverse sectional view alongline 5-5 of-` Fig. 1. Fig.6 is a transverse sectional view on an enlarged'scale of'one of thestationary pistons alongthe line 6-6 of Fig. 3; and

1 plate as shown.

and G are connected by means of suitable cross-heads withconnecting-rods H and H" mounted on pin I on crank J on the main shaftF. Within working pistons G, G

are mounted stationary pistons K, K supported an conduits or pipes L, L,L, L, and L', L L', L respectively, the conduits or pipes L and L beingmounted in the base plate D2 of crank case D. The stationary pistons Kand K are adjustable with relation to their supporting conduits or pipesso as to increase or decrease the size of the compression chambers M,M"formed between the top of working pistons G, G and I stationarypistons K, K, such adjustment being attained by means ot suitableadjusting nuts N adapted .to clamp fixed pistons K, K 'to the conduitsor pipes L, L respectively, las is clearly shown inFig. 6.

- In base plate D2 of crank case D are cast passages D3 and D4 whichcommunicate respectively with conduits or pipes L and L'.

Passage D3 connects with a pipe O forming the air inlet controlled by anordinary check valve O". Passage D4 connects with a pipe O2communicating with the Vcarbureter and controlled by an ordinary checkvalve O3. The conduits or pipes L and L and the passages D3 and D4 areduplicates of each other and arranged onopposite sides of the base Theheads Gr2 and Graef the lworking pistons G and G" are screwed into theends of the working pistons and 1:5. metteva each of them is ber asshown.

The cross-heads for connecting-rods H and H with working pistons G and Gare mounted in the lower part of pistons G and G in the usual manner andin such a position that they do not interfere with the conduits or pipesL, L.

P is a chamber in the wall of the left hand cylinder to act as anexhaust chamber and is connected by a pipe P to a mui'ller (not shown)or to the open air.

P2 is a circumferential slot forming a means of communication betweencylinder A and exhaust chamber P. In the wall B, between cylinder A andA is cast a passage Q forming a means of communication between the two'cylinders A yand A. In working piston G thereis a port or opening Radapted to register at the lower end of the provided with an airchamstroke with one end of the passage Q so,

that the'contents of the compression chamber M may pass at that time tothe right hand cylinder A. In the wall of the right hand cylinder isformed a passage R and in the wall of working piston G there is a portor opening R2 adapted to register at the lower end of the stroke withthe lowei` end of passage R so that the contents of the compressionchamber M may pass over head G3 of working piston G and into explosionchamber C as isclearly shown in Fig. 3.

S is alspark plug of any suitable construction, T the water inlet forthewater jacket or chamber inthe walls of the cylinders and T the wateroutlet for the same.

The operation of the device is as follows: A charge being previouslyintroduced and compressed in explosion chamber Cisfred in the usual wayby the spark plug S. Both working pistons G and G descend under theforce of the explosion until working piston G passes the slot P2communicating with the exhaust chamber P, allowing the contents of bothcylinders to exhaust into chamber P and thence through pipe P. Theopening P2 between exhaust chamber P and the interior of the cylindersis of considerable size, and circumferential with relation to thecylinders. Due to the size of this opening into exhaust chamber P thedescent of' working piston G uncovers the same very rapidly before theport Rs in said piston registers with passage Q. The burnt gases in bothcylinders therefore will escape to a large extent into exhaust chamber Pbefore /the port R registerswith passage Q. The

compression chamber M contains air only and this air is considerablycompressed by the descent of the Working piston G, the check Valve Oclosing; so that when the port R of working piston G registers withpassage Q, the compressed air will rush through the passage Q into theright hand cylinder driving the residue of the burnt gases cut throughconduits L', passage D* and pipe 02/70 is connected with a. suitablecarbureter containing a charge of air mixed with 'gasolene or othercombustible vapor which is drawn in by the upward movement of workingpiston G through conduits L as described. Then working piston G descendsthe checkvalve O3 closes and the charge is compressed in chamber M untilby the descent of working piston G the port R2 in said piston registerswith the lower opening of passage R', whereupon the compressed chargewill pass from the compression chamber M through passage R over head G3into explosion chamber C. -l

It will be observed that this passage of the charge from thevcompression chamber M is subsequent to the scavenging of the cylindersby the air from compression chamber M. The charge following the air isdirected by a baffle plate .G4 formed as a part of head G3 to theI upperpart nf explosion chamber C. The contents of the chambers M and M beingequal or nearly equal to the contents of the explosion chamber C, theentire portion of the burntgases will be expelled into exhaust chamberP, leaving the mixture of air or gaseous Vapor nearly or quite pure. f

It will also be observed that at the time of the discharge from chamberM into explosion chamber C the slot P2 connecting the interior of thecylinder with exhaust chamber P is partly closed allowing just aSullicient opening for any" residue of burnt gases to escape. v

The revolution of the main 'crank sha-ft F now carries working pistons Gand G upward, compressing the charge. As the Working pistons G and Gmove upward air is drawn in by suction past check valve O into chamber Mand air and gas'in a suitable mixture are drawn into chamber M pastcheck valve O3 as described. As working pistons G and G descend checkvalves 0 and O3 as described are closedso that the contents of chambersM and M may be compressed by the movement of the working pistons. Inthis cycle it will be observed that there is a power impulse at everydown- Ward or'outward movement of the working pistons from the explosionchamber, that at the end of the power impulse when nearing the extrememotion of the working pistons the exhaust from both cylinders firsttakes place, then a scavenging action bv the air compressed in chamber Mand finally the introduction of a charge of air and vapor fromcompression chamber M.

The above mentioned results are obtained through the use of twocompression chambers and the differential movement of working pistons Gand G. This differential movement by which the working piston G arrivesat the lilnit of its motion a little in advance of the working piston Gandbegins its return also a little in advance enables the ports to beuncovered and closed so as to obtain the successive actions abovedescribed.

It will be observed that there is a volume of air between the charge andthe burnt gases and that the pressure of the compressed charge drivesthe air ahead of it and the burnt gases ahead of the air, so that if asmall portion of air escapes at the exhaust chamber P no harm will bedone. This enables the exhaust port between the cylinders and theexhaust chamber P and the exhaust chamber itself to be made ofconsiderable size so as to allow a complete and thorough exhaustion ofthe burnt gases while at the same time a pure mixture of air and gas isprovided for compression and combustion.

I am aware that I am not the first to use the twin cylinderconstruction, and that I am not thefirst to use a compression chamber onthe inside of a hollow piston. I am also aware that I am not the lirsttouse a differential motion of the pistons in such twin cylinderconstruction, but I believe myself to be the first to use thecompression chambers in connection with the twin cylinder'constructionand to obtain the differential action of the pistons by off-setting thecylinders with reference to the crank shaft. I also believe myself to bethe first to mount a stationary piston directly on pipes o1 conduitscommunicating with a compression chamber, and to mount these pipes orconduits directly upon a crank case.

There are great advantages in this method of construction: it beingsimple. cheap and accessible. The pipes and conduits L and L may besteel pipes screwed into the base plate D2. n

The stationary pistons I prefer to make in the form shown in Figs. 6 and7. By .the use of bolts, these pistons can be easily brought into exactalinement with the working pistons and fastened there. It' is alsopossible by this means of adjustment, within certain limits, to increaseor decrease the size of the compression chambers M and M.

It is possible` by my improved construction, to obtain the advantages ofa power impulse at every complete revolution of the crank shaft: at thesame time to'fscavenge the cylinders by means of air under considerablecompression. and to provide. a pure or nearly pure mixture of air andgas for `compression and explosion` and to obtain these advantages withthe fewest number of moving parts.

Itvwill also be noted that it is almost impossible for a back fire tooccur with the construction which I have shown. At no time is there anydirect communication between the burnt gases and the incoming charge Theair passing from the chamber M, is much cooler than the gases which itexpels, and has a cooling effect upon the walls of the cylinder.

It will also be noted that the charge which is drawn into the chamberM', comes into this chamber at atmospheric pressure, is considerablycompressed, then discharged through the passage R, and'finallyrecompressed in explosion chamber C at the upper movement of the twoworking pistons, thereby giving a more-thorough mixture of the air andgas than can be obtained in the ordinary two cycle engine. The heatingof the air by compression as the piston G descends, also helps to makethis mixture.

I have shown only one power unit, but it is obvious that for use inautomobiles or motor boats and other constructions, two or more suchpower umts as shown might be used. As a matter of comparison, it may besaid that three such twin cylinders used in an automobile would give thesame torque as is now obtained in a G-cylinder engine of thefour cycletype, and at the same time avoid the use of valves. cam shafts withtheir gears, cams and'other parts necessary in such a construction.

It is also tobe understood that I may use the form of compressionchamber lnade by mounting a stationary piston inside of a hollow pistonand mounting said stationary piston on conduits, in connection with asingle cylinder instead of a twin cylinder as previously described. Insaid last nalned construct-ion, the compression chamber would receive acharge of air and gas. and it would be delivered directly above theworking piston by a passage similar to that shown in the right handcylinder of Fig. 1.

It is also to be understood that while I have embodied my invention ginthe best form now known to me, that I`do not confine myself to the exactmechanical details disclosed which may be widely varied withoutdeparting from the principles shown.

It will be observed that because of working pistons G and G being openat the lower endand communicating directly with the crank case. theordinary method of splash lubrication may be utilized and that throughthis means all working parts of the engine will be sufficiently'lubricated in the easiest and most effective manner.

It will further be observed that by disconnecting bolts D'. D'. thewater connections T and T and the exhaust pipe I, the cylinders can-belifted from the crank case thereby exposing the working pistons andassociated parts rendering them easy of inspection and repair.

In the specification and claims where I referto a twin cylinder I meantwo cylinders having a common combustion head and so arranged that bothcylinders may be exhausted and charges introduced into both `cylindersfrom a port in either cylinder.

Such a twin cylinder may be of two separate castings with connectingpassages or in a single casting as shown in the drawings. In such a twincylinder construction the connecting-rods from the working pistons areconnected to the crank shaft at substantially the same point of thecrank shaft revolution and where I refer to a common driving shaft Imean to refer to such construction.

lVhat I claim and desire to secure by Letters Patent is:

1. In an internal combustion engine, the combination of a cylinder, anexhaust in the wall of said cylinder, ahollow working piston. astationary piston within the working piston. a compression chamberbetween said working piston and said stationary piston and conduits onwhich said stationary piston is mounted, said conduits being adapted toconvey air or gas to said compression chamber.

2. In an internal combustion engine. the combination of a cylinder, ahollow Working piston. a stationary piston within the working piston. acompression chamber between said working piston and said stationarypiston and conduits on which said stationary piston is adjustablymounted whereby the size of the compression chamber may be varied, saidconduits being adapted to convey air or gas to said compression chamber.

3. In an internal combustion engine, the combination of a cylinder, anexhaust chamber in the wall of said cylinder. a circumferential slotconnecting said cylinder with said exhaust chamber, a hollow workingpiston adapted lto uncover and cover said slot, a stationary pistonwithin said working piston. a compression chamber between said workingpiston and said stationary piston and conduits on which said stationarypis- -ton is mounted, said conduits being adapted to convey air or gasto said compression chamber.

4. In an internal combustion engine, the combination of a twin cylinder,a common explosion chamber for said cylinders, a working piston in eachof said cylinders, a common driving shaft oiiset with relation to saidpistons and rods connecting said shaft and said pistons. whereby saidpistons are given a diderential motion during the revolution of thedriving shaft.

5. In an internal combustion engine, the combination of a' twincylinder, a common explosion chamber for said cylinders, a hollowworking piston in each of said cylinders,

messia a common driving shaft offset with relation to said pistons, astationary piston. Within each of said working pistons and a compressionchamber between each of said working pistons and said stationarypistons.

6. In an internal combustion engine, the combination `of a twincylinder, a common explosion chamber for said cylinders, a hollowworking piston in each of said cylinders, a common driving shaft offsetwith relation to said pistons, a stationary piston within each of saidworking pistons, a compression chamber between each of said workingpistons and said stationary pistons and conduits on which saidstationary pistons are mounted, said conduits being adapted to conveyair or gas to said compression chambers.

7. VIn an internal combustion engine, the combination of a twincylinder, a common explosion chamber for said cylinders. a hollowworking piston in each of said cylinders, a common driving shaft forsaid pistons, a stationary piston within each of said working pistons. acompression chamber between each of said working pistons and saidstationary pistons and conduits on which said stationary pistons areadjustably mounted whereby the size of the compression chamber may bevaried, said conduits being adapted to conveyair or gas to saidcompression chambers.

8. In an internal combustion engine, the combination of a twin cylinder,a common explosion chamber for said cylinders. a hollow working pistonin each of said cylinders, a common driving shaft' for said pisf tous, astationary piston within each of said working pistons, a base plate,conduits mounted in said base plate and in turn supporting thestationary-pistons and air and gas inlets in the base plate connectingwith said conduits.

9. In an internal combustion engine, the combination of a twin cylinder,a common explosion chamber for said cylinders, passages for air and gasthrough the walls of said cylinders, a hollow working 'pist-on in eachof said cylinders, ports in said working pistons adapted to registerwith said passages for air and gas, a stationary piston within each ofsaid working pistons. a compression chamber between each of said workingpistons and said stationary pistons and conduits on which saidstationary pistons are mounted. said conduits being adapted to conveyair or gas to said compression chambers.

c 10. In an internal combustion engine. the combination of a cylinder.ahollow working piston open at one end within said cylinder, astationary piston Within said working piston, a compression chamberbetween said working piston and said stationary piston,

conduits on which said stationary piston is mounted, said conduits beingadapted to convey air or gas to said compression chamber and a crankcase upon which said conduits are mounted.

11. In an internal combustion engine, the combination of a cylinder, ahollow working piston open at one end within said cylider, a stationarypiston within said working piston, conduits on which said stationarypiston is mounted, a crank case in which said conduits are mounted andair and gas inlets in said crank case connecting with said conduits.

12. In an internal combustion engine, a twin cylinder, a hollow workingpiston in each of said cylinders, a common explosion chamber for saidcylinder, passages through the walls of said cylinder for the exhaust,air scavenging charge and explosive mixture charge respectively, portsin said working pistons adapted to register with the air scavengingcharge vpassage and explosive mixture charge passage respectively, saidexhaust, air scavenging control andnexplosive mixture control beingbrought into action successively by the movement of the working pistonswhich successively uncover and cover the openings in the said exhaust,air scavenging passage and explosive mixture passage.

13. In an internal combustion engine, a twin cylinder, a commonexplosive chamber for said cylinder, a hollow working piston in each ofsaid cylinders, an exhaust, air scavenging passages and explosivemixture passage through the walls of said cylinder, and ports in saidworking pistons adapted to register with said air scavenging passage andexplosive mixture passage, one of said working pistons being adapted touncover and cover the exhaust and to introduce the air scavenging charge and the other of said working pistons being adapted to introducethe explosive mixture charge.

14. In ,an internal combustion engine, a twin cylinder, a commonexplosion chamber in said cylinder, an exhaust from said cylinder, ahollow working piston in each of said cylinders, an air scavengingpassage through the wall of said cylinder controlled by the movement ofone of said working pistons and brought into operation while the exhaustis open and` after the burnt charge has passed of and an explosivecharge passage through the wall of said cylinder controlled by themovement of the other of said working pistons and brought into actionupon the closure of the air scavenging passage. u

15. In an internal combustion engine, the combination o a twin cylinder,two working pistons, two compression chambers, an

y exhaust port, and ports in the cylinders and working pistons adaptedto register so that the'movement-of the pistons will cause in successionthe discharge of the burnt gases, the scavenging of air and theintroduction of a charge of air and gas for subsequent compression' andexplosion.

16. In an internal combustion engine, the combination of a twincylinder, two working pistons, stationary pistons in the Workingpistons, two compression chambers, an exhaust port, and ports in thecylinders and working pistons so arranged that the movement of theworking pistons will cause in succession the discharge of the burntgases, the scavenging of thecylinders by air and the introduction of acharge of air and gas for subsequent compression and explosion.

17. In an internal combustion engine, the

combination of a twin cylinder, two Working pistons, stationary pistonsin the working pistons, two compression chambers, an exhaust port, portsin the cylinders and working pistons and a crank shaft connected to theworking pistons, said crank shaft being oiset so as to cause adifferential y movement of said pistons adapted to cause in succession adischarge of the burnt gases, the scavenging of the cylinders by air andthe introduction of a charge of air and gas for subsequent compressionand explosion. 18. In an internal combustion engine, the combination ofa cylinder, an explosion chamber, a piston and a compression chamberadjustable in size within said piston, said compression chamber lyingwholly above the connection of the piston with the connecting-rod,whereby a relatively high degree of compressionmay be obtained.

19. In an internal combustion engine, the combination of twin cylinders,two compression chambers, an exhaust port and inlet ports withdiierentially moving pistons forming one side of said compressionchambers and in their movement operating to control said ports.

20. In an internal combustion engine, the combination of twin cylinders,a common explosion chamber, a' piston in each of said cylinders andmeans in each of said pistons shaft offset with relation to saidpistons, a compression chamber lying vwholly within each of said pistonsand means by which the reciproeation of the pistons will alternatelydraw in and compress a charge of air or gas.

23. In an internal combustion engine, the combination of a twin cylinderwith a working piston in each of said cylinders, a common driving shaftoffset with relation to said pistons, and a fixed piston adapted tocooperate with each of saidworking pistons to obtain a high compressionof a charge of air or gas.

:24. In an internal combustion engine, the combination of a twincylinder with a working pist-on in each of said cylinders and anadjustable fixed piston adapted to coperate with each of said workingpistons to obtain a high compression of a charge of air or gas.

In an internal combustion engine, the combination of a twin cylinder, acommon explosion chamber, a piston in each of said cylinders, a commondriving shaft oHset with relation to said piston, a. separatecompression chamber coperating with each of said pistons, an exhaustport and inlet ports, saidpistons being adapted to be operateddifferentially to control said exhaust and inlet ports.

:26. In an internal combustion engine, thel combination of a twincylinder, al common explosion chamber, a piston in each of saidcylinders, a separate compression chamber coperating. with each of saidpistons, an exhaust port and inlet ports, said pistons being adapted tobe operated differentially to close said exhaust port,'either wholly prin part, before opening the inlet port for the gaseous charge.

27. In an internal eombustion'engine, the combination of a twincylinder, aV common explosion chamber, a piston in each of saidcylinders, a compression chamber coperating with each of said pistons,an exhaust port and inlet ports, one of said pistons being adapted tocontrol the exhaust port and the other the gas inlet port, and means foroperating the pistons differentially whereby the exhaust port is closed,in whole or in part, before the opening of the gas ,inlet ort. p 28. Inan internal combustion engine, the combination of a twin cylinder, apiston for each cylinder, an exhaust port and air and gas inlet ports,said pistons being adapted to move differentially and to control theports so as to cause in succession the opening of the exhaust port, theopening of the air inlet port, the closing of the exhaust port, inwholeorin part, and the opening of the gas inlet port.

29. In an internal combustion engine, the combination of a twincylinder, a piston for each cylinder, a compression chamber cooperatmgwlth each plston, an exhaust port,

y/and air and gas inlet ports from said comport, in whole or in part.and the opening of the gas inlet port.

' 30. In an internal combustion engine of the two-cycle type, thecombination of pistons and compression chambers so coperating with'eachother as to cause in succession the exhausting of the burnt gases, thescavenging of the residue of the burnt gases, the closing of the exhaustopening, in whole or in part before the introduction of a fresh charge,the introduction of a fresh charge and the compression of said chargefor subsequent tiring.

31. In an internal combustion engine of the twoscycle type, thecombination of a crankshaft, connecting rods and pistons as the onlymoving parts, and an exhaust port -and inlet ports, said pistons beingadapted to be operated differentially to control said exhaust and inletports, in cooperation with compression chambers so arranged as to causein succession the exhausting 'of the burnt gases, the scavenging of theresidue 'of burnt gases, the closing of the exhaust opening, in whole orinpart before the introduction of a fresh charge, the introduction of afresh chargeand the compression of said charge for subsequent firing,

3:2. In an internal combustion engine of the two-cycle type, the exhaustand inlet ports of which are controlled solely by the movement of thepiston or pistons, means for closing the exhaust port in Whole or inpart before the openingr of the inlet port for the fresh charge. y

33. In an internal combustion engine, the combination of a cylinder, apiston open at one end, a crank shaft, a connecting rod between saidpiston and crank shaft and an adjustably mounted fixed piston locatedbetween the top of the first named piston and the point of connectionbetween said piston and the connecting rod.

34. In an internal combustion engine, the combination of a cylinder, apiston open at one end, a crank shaft, a connecting rod between saidpiston and crank shaft, an adjustably mounted xed piston located be--inders, a. crank shaft, aconnecting rod betweeneach of said pistons andthe crank shaft and a normallv fixed piston in eachI of said cylinderslocated between the top of the first named piston therein and the pointof connection betweensaid piston and the connecting rod.

36. In an internal combustion engine, the

vcombination of a plurality of cylinders, a-

piston open at one end in each of said cylinders, ,a crank shaft, aconnecting' rod-between each of said pistons andthe crank shaft and anadjustably mounted ixed pis'- ton in each of said cylinders locatedbetween the top of the irst named piston therein and the point ofconnection between said piston and the connecting rod. v l 37. Inan'internal combustion engine, the

combination of a plurality of cylinders, a piston open at one end ineach of said cyl-l inders, a crank shaft offset with relation to saidpiston, a connecting rod between each of said pistons andthe crankshaft, a normally xed piston in each of said cylinders located betweenthe top of the first named lpiston open at one end in each of said cyl?inders, a crank shaft, a connecting rod loe-Ak `tween eachrof saidpistons and the crank `shaft'an adjustably mounted iXed piston in eachof said cvlinders located between the top of the first named pistontherein and the vpoint of connection between said piston and theconnecting rod and supporting means for each of said fixed pistons outof the path of the connectingrod.

In testimony whereof have signed this.

specification in the presence of two subscribing witnesses.

Witnesses:

K. G. LEARD, JOHN HERR.

'JoHN n. ROGERS.'

